package com.itheima.reggie.controller;

import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

/**
 * @PackageName:com.springboot.reggie.controller
 * @ClassName:commonCtroller
 * @Description: 文件的上传和下载
 * @Author: U87
 * @Date:2022/4/27 14:50
 */
@Slf4j
@RestController
@RequestMapping("/common")
public class commonCtroller {
    @Value("${reggie.path}")
    private String basePath;

    //文件上传
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file) {
        //file是一个临时文件,需要转存到指定位置,否则本次请求结束 临时文件会删除
        //原始文件名字
        String originalFilename = file.getOriginalFilename();
        String substring = originalFilename.substring(originalFilename.lastIndexOf("."));
        //使用uuid重新生成名字,防止文件名字重复覆盖文件.
        String fileName = UUID.randomUUID().toString() + substring;
        //创建一个目录
        File dir = new File(basePath);
        if(!dir.exists()){
            dir.mkdir();
        }
        try {
            file.transferTo(new File(basePath + fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }
        return R.success(fileName);

    }
    //文件下载
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response) {
        try {
            //输入流 读取文件内容
            FileInputStream fileInputStream = new FileInputStream(new File(basePath + name));
            //输出流,把文件写回浏览器
            ServletOutputStream outputStream = response.getOutputStream();
            response.setContentType("image/jpeg");

            int len = 0;
            byte[] bytes = new byte[1024];
            while ((len = fileInputStream.read(bytes)) != -1) {
                outputStream.write(bytes, 0, len);
                outputStream.flush();
            }
            outputStream.close();
            fileInputStream.close();

        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }
}
